Asbestos Related Lung disease

Related Subjects: | Idiopathic Pulmonary Fibrosis | Diffuse Parenchymal Lung disease | Asbestos Related Lung disease | Sarcoidosis | Coal Worker's Pneumoconiosis | Silicosis | Farmer's Lung | Cryptogenic Organising Pneumonia (COP-BOOP) | Extrinsic Allergic alveolitis (Hypersensitivity) | Byssinosis | Pneumoconiosis | Cor Pulmonale

Asbestos exposed patients must stop smoking if they do not wish to reduce risks of cancer.

Pleural plaques - resemble candle wax dripping

Mesothelioma encasing lung

About

• Asbestos is a collection of naturally occurring fibrous silicates with remarkable insulating properties
• Asbestos fibres are strong, heat and chemical resistant and do not dissolve in water or evaporate
• Boiler making to lag pipes, shipbuilding, construction industry, heat resistant paints and brake pads etc
• Due to the risks to health following inhalation exposure to asbestos the importation of blue and brown asbestos has been banned in the UK since 1985. This ban was extended to include white asbestos in 1999.
• Asbestos is not considered harmful when in large pieces and undamaged
• Damaged asbestos can release smaller fibres that can be breathed in or swallowed

Types of Asbestos

• Serpentine: Chrysolite - White is the most common and least fibrogenic
• Amphibole: Crocidolite (blue), Amosite (Brown): More hazardous
• All forms of asbestos fibres are hazardous as they can induce cancer following inhalation exposure, but amphibole forms of asbestos (including blue and brown) are more hazardous to health than chrysotile (white).

Clinical Manifestations of Asbestos exposure(most take decades to present)

• Asbestos bodies: seen in sputum serve only as a marker of exposure
• Pleural plaques: seen in 50% of those exposed and only suggest asbestos exposure and of themselves mean little else.
• Pleural thickening: may cause a restrictive defect and increased dyspnoea
• Pleural Mesothelioma:A progressive and aggressive tumour that can encase the lung. Patients with mesothelioma classically present with a dull ache and breathlessness and chest pain. There is no effective treatment and the prognosis is poor. Can be seen even with relatively low-level exposure
• Peritoneal mesothelioma a rapid relentlessly lethal tumour
• Bronchial carcinoma: More commonly adenocarcinoma but also squamous cell carcinoma are associated with asbestos exposure. Smoking is additive.
• Asbestosis: A sign of heavy asbestos exposure. Usually mild and takes 20-30 years to occur. Increasing dyspnoea, finger clubbing and end-inspiratory crackles. Increased risk of lung cancer.

Investigations

• CXR - pleural changes. Fibrosis. The effusion may suggest pleura disease
• Pulmonary function tests identify a restrictive defect
• HRCT - can show parenchymal and pleural disease
• Bronchoscopy to look for tumours

Management

• As above.